Shahov A S, Dugina V B, Alieva I B
Tsitologiia. 2015;57(3):222-32.
Endothelial cells are tightly fitted to each other and lining the interior surface of all vessels of living organism to provide vascular permeability regulation and interchange between the blood circulating in vessels and tissue fluids of those organs in which these vessels are located. In vitro endothelial monolayer conserve it's basic barrier function which is native for vessels endothelium. Based on this fact we used endothelial cells growing in vitro as a model system in experimental studies of cytoskeletal and adhesion cell components interaction. In current paper, cultured human vein endothelial cells monolayer was used to quantify cytoskeleton alterations in the of endothelial cells from spreading and formation of the first cell-cell contacts to confluent monolayer formation. The system of actin filaments formed two different cytoskeletal structures in the cells of venous endothelium: 1) cortical actin network; 2) actin stress fibers (bundles) arranged parallel to the substrate. Two actin isoforms, β- and γ-cytoplasmic (non-muscle) actins, are expressed in endothelial cells. The bundles of actin stress fibers were detected by immunofluorescent staining with antibody against β-actin, whereas antibodies against γ-actin identified cortical and lamellar networks. For assessment of the actin cytoskeleton organization it's fluorescence intensity on the area of 10 μM2 located (1) near the free edge, and (2) in the zone of cell-cell contacts were analyzed. Fluorescence intensity of β-actin structures was higher in the areas of cell-cell contact. The fluorescence of γ-actin structures was more intensive at the leading edges of the lamellae, and was the lowest on the stable edges of the cells with formed cell-cell contacts. The endothelial monolayer formation was accompanied by microtubule system alteration: the number of microtubules increased at the cell edge, and besides the microtubules quantity in the area of already formed cell-cell contact was always higher than in free lamella region.
内皮细胞彼此紧密贴合，衬于生物体所有血管的内表面，以调节血管通透性，并在血管中循环的血液与这些血管所在器官的组织液之间进行物质交换。体外培养的内皮细胞单层保留了其血管内皮固有的基本屏障功能。基于这一事实，我们在细胞骨架和黏附细胞成分相互作用的实验研究中，将体外培养的内皮细胞用作模型系统。在本论文中，培养的人静脉内皮细胞单层被用于量化从细胞铺展和最初的细胞 - 细胞接触形成到汇合单层形成过程中内皮细胞的细胞骨架变化。肌动蛋白丝系统在静脉内皮细胞中形成了两种不同的细胞骨架结构：1）皮质肌动蛋白网络；2）平行于底物排列的肌动蛋白应力纤维（束）。两种肌动蛋白异构体，β - 和γ - 细胞质（非肌肉）肌动蛋白，在内皮细胞中表达。通过用抗β - 肌动蛋白抗体进行免疫荧光染色检测到肌动蛋白应力纤维束，而抗γ - 肌动蛋白抗体则识别皮质和片状网络。为了评估肌动蛋白细胞骨架的组织情况，分析了位于（1）自由边缘附近和（2）细胞 - 细胞接触区域的10 μM²面积上的荧光强度。β - 肌动蛋白结构的荧光强度在细胞 - 细胞接触区域更高。γ - 肌动蛋白结构的荧光在片状伪足的前沿更强烈，而在已形成细胞 - 细胞接触的细胞稳定边缘处最低。内皮单层的形成伴随着微管系统的改变：微管数量在细胞边缘增加，而且在已经形成细胞 - 细胞接触的区域微管数量总是高于自由片状区域。
